Hey Jono

there are a few reasons . One was that i never used enough dye to keep the colour in there for long, i did this on purpose because i dont like putting anything in my fuel that isnt absolutely nessesary .. the problem was that it would fade . We have since changed brand of dye and its holding fast . The good news is we use half as much as before and it does the job really well. Hope this helps .. the piss yellow colour is what the fuel looks like before the dye ..

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